for many, taking seroquel xr with an antidepressant was proven more effective than an antidepressant alone for treating unresolved symptoms of depression. talk to your doctor about seroquel xr. then visit seroquelxr.com for a free trial offer. call your doctor if you have unusual changes in mood, behavior, or thoughts of suicide. antidepressants can increase these in children,teens, and young adults. elderly dementia patients taking seroquel xr have an increased risk of death. call your doctor if you have fever, stiff muscles, and confusion, as these may be signs of a life-threatening reaction or if you have uncontrollable muscle movements, as these could become permanent. high blood sugar has been reported with seroquel xr and medicines like it and in extreme cases can lead to coma or death. your doctor should check for cataracts. other risks include decreases in white blood cells, which can be fatal, seizures, increased cholesterol, weight gain, dizziness on standing, drowsiness,impaired judgment, and trouble swallowing.